Adjective

(en adjective)

Without fault or weakness; incapable of error or fallacy.

He knows about many things, but even he is not infallible .

certain, sure.

* {{quote-book

, year=1818 , author=Mary Shelley , title=Frankenstein , chapter=4 citation , passage=I see by your eagerness and the wonder and hope which your eyes express, my friend, that you expect to be informed of the secret with which I am acquainted; that cannot be; listen patiently until the end of my story, and you will easily perceive why I am reserved upon that subject. I will not lead you on, unguarded and ardent as I then was, to your destruction and infallible misery.}}

Adjective

(en adjective)

Exact, accurate.

*

(sciences) Of experimental results, consistent, clustered close together, agreeing with each other. This does not mean that they cluster near the true, correct, or accurate value.

* {{quote-magazine, date=2013-06-22, volume=407, issue=8841, page=76, magazine=(The Economist)

, title= Snakes and ladders , passage=Risk is everywhere.